Crankshaft twisting machine



Feb. 20, 1951 A. K. NowAK CRANKSHAF'T TWISTING MACHINE 7 Sheets-Sheetl lFiled Aug. 5, 1947 Feb. 20, 1951 A. K. NowAK 2,542,050

CRANKSHAFT TwIsTING MACHINE Filed Aug. 5, 1947 '7 sheets-sheet 2 A. K.NOWAK CRANKSHAFT TWISTING MACHINE Feb. 20, 1951 7 Sheets-Sheet 3 FiledAug. 5, 1947 www - Feb. 2o, `1951 A, K, NOWAK 2,542,050

CRANKSHAFT TwIsTING MACHINE Filed Aug. 5, 1947 7 sheets-sheet 4 Feb. 20,1951 A, K, NOWAK 2,542,050

CRANKSHAFT TWISTING MACHINE Filed Aug. 5, 1947 7 Sheets-Sheet 5 Feb. 20,1951 A. K. NowAK 2,542,050

CRANKSHAFT TWISTING MACHINE Filed Aug. 5, 1947 "7 Sheets-Sheet 6 Feb.zo, 1951 A K, NOWAK 2,542,050l

CRANKSHAFT TWISTING MACHINE Fi1ed Aug. 5, 1947 7 sheets-'sheet 7Patented Feb. 2o, i951 CRANKSHAFT TWISTING MACHINE Alois K. Nowak,Evanston, Ill., assigner to Clearing Machine Corporation, Chicago, Ill.,a corporation of Illinois Application August 5, 1947, Serial No. 766,369

Claims.

This invention relates to machines for manufacturing crank shafts forengines, and to the method of manufacturing such crank shafts.

An important object of the invention is to provide a new and improvedmachine which will operate upon a forged crank shaft to properly twistthe crank pins of the shaft and accurately to locate the pins accordingto the design and type of the crank shaft.

Another and important object of the invention is to provide a novelmachine for twisting crank shafts, the machine including upper and lowerdie members adapted to clamp a forged crank shaft in place and thentwist the crank pins of the shaft to locate them properly.

A further object of the invention is to provide a crank shaft twistingmachine wherein a lower die member is adapted to receive a forged crankshaft, and an upper die member which is adapted to be brought againstthe lower` die to clamp the crank shaft in place, movable dies beingcaused to twist the crank pins ofthe shaft in a predetermined manner forproperly locating the crank pins in the nal shaft after the upper andlower dies have clamped the shaft.

Still another object of the invention isfto provide a hydraulicallyoperated crank shaft twisting machine having upper and lower diemembers, each of which includes movable and stationary dies to clamp aforged crank shaft in place, the movable dies being rotated in apredetermined manner to twist the crank shaft and properly position thecrank pins thereon after the shaft is clamped in position.

A still further object is to provide upper and lower die members, eachof which includes movable and stationary dies, the upper and lower diesbeing complementary and clamp the forged crank shaft in place within thedies; the movable die members being adapted to cause thel various crankpins of the crank shaft to be twisted about predetermined axes toposition properly the crank pins. Y

Another object is to provide a crank shaft twisting machine which ishydraulically operated, and which is provided with a singlehydraulically operated lever arm, the actuation of which lever armproducing successive twisting operations on the forged crank shaft.

Still another object of the invention is the method of4 forming ortwisting a crank shaft in aV predetermined manner according to apredetermined sequence to effect the proper twisting of the shaft and toobtain the pins thereon in proper alignment.

Numerous other objects and advantages of the invention will becomeapparent upon reading the following description taken in conjunctionwith the accompanying drawings in which:

Fig. 1 is a front elevational View of a machine embodying the principlesof the present invention;

Fig. 2 is a side elevational view of the machine illustrated in Fig. 1;

Fig. 3 is an enlarged sectional View through the upper and lower dies ofthe machine showing the dies in closed position and a forged crank shafttherein;

Figs. ,4, 5, 6 and 7 are diagrammatic illustrations of the successivetwisting operations performed upon a 'crank shaft; Fig. 4 illustratingthe original position of the .crank shaft; Fig. 5 illustrating thepositions of the various crank pins at the end of the first twistingoperation; Fig. 6 showing the positions of the various crank pins at theend of the second twisting operation; and Fig. 7 showing the positionsof the various crank pins at the completion of the final twistingoperations;

Fig. 8 is a vertical sectional view through the machine showing theupper and lower dies in separated position;

Fig. 9 is a vertical sectional view through the machine showing theupper and lower dies in engagement, and illustrating the position of thevarious crank pins at the end of the rst twisting operation;

Fig. 10 is a vertical sectional view through the f end bracket of thelower die in the position it assumes at the end of the first twistingoperation;

Fig. 11 is a view similar to Fig. 9, but showing the various parts ofthe dies, and the positions of the crank pins, at the end of the finaltwisting operation;

Fig. 12 is a view similar to Fig. 10 showing the position of the variousparts at the end of the final twisting operation; and

Fig. 13 is a vertical sectional View through the machine at the end ofthe twisting operation with the upper and lower dies separated; saidview also showing a twisted crank shaft being ejected from the machine.

The crank shaft twisting machine of the present invention isparticularly directed to the twisting of a 6-pin crank shaft havingthree throws, as distinguished, for example, from crank shaft twistingmachines heretofore designed for shafts having four pins. The problemsencountered in a crank shaft having three throws are much 3 moredifficult to overcome than crank shafts having a lesser number.

The present invention comprises, in general, a hydraulically operatedmachine having upper and lower dies. A forged crank shaft is adapted tobe placed in a lower die where certain of the bearings thereon areclamped and held against movement. The upper die is brought downwardlyagainst the lower die and is complementary therewith so that the crankshaft may be held in place in its entirety. The upper and lower diesconsist of a stationary die, inner rotating dies and outer rotatingdies. A single hydraulically actuated lever arm is fastened to the innerrotating dies, and a system of interlocks is provided so that a singlestroke of the lever arm will rotate the inner and outer rotating diessuccessively to perform the necessary twisting operations upon the crankshaft.

The machine illustrated herein, Figs. 1 and 2, is of the portable type,capable of being moved from piace to place, although the operation ofthe machine, and the invention embodied therein, is applicable to astationary machine as well.

A bed I is provided at the lower part of the machine, and this bed hasuprights 2 extending upwardly therefrom, a crown 3 being provided at thetop of the uprights. A slide 4 is adapted to reciprocate vertically inguideways 5 by any suitable control of a hydraulic fluid from a cylinderThe hydraulic fluid is forced to flow through the various conduitsprovided therefor by means of a pump '5. Any suitable hydraulic systemmay be utilized for causing operation of the machine, and since thehydraulic system per se forms no part of the present invention, thesystem is not being illustrated herein in detail.

A lower die member 8 is positioned on the bed I, and an upper die member9 is carried by the slide A forged crank shaft is placed in the lowerdie 3 after which the upper die 9 is brought into contact therewith andthe twisting operation is begun. The lower die 8 comprises a stationarydie l@ and outer rotating dies I I andY I2. These outer rotating dies IIand I2 are provided with pivot pins I3 and Il! respectively on whichthese dies rotate. Fig. 3 illustrates a sectional view through the twodie members 8 and 9 in their closed position, and shows the crank shaftin plan.

Several pairs of rollers I5, I6, ll and I8 are mounted rotatably on thebed I, and below the lower die S on which the lower curved surface ofthe lower die may rest to facilitate the rotation thereof during thetwisting operation.

Each of the outer rotating dies II and I2 is provided with an outerupwardly extending portion l@ through which a pin 2i) extends for thepurpose of supporting a twisting die 2| for the end bearings of thecrank shaft. An end bearing locating lever 22 is secured to the uprights2 at each end of the lower die member. The inner rotating dies 23 and 24are located within the outer rotating dies II and I2.

The upper die member 8 includes inner rotating dies 25 and 26 which areadapted to cooperate with the inner rotating dies 23 and 24 of the lowerdie member when the upper and lower die members are brought togetherduring the twisting operation. The upper die member 9 also includesouter rotating dies 21 and `28 which cooperate with the outer rotatingdies II and I2 of the lower die member 8 during the twisting operation.A stationary die 29 also is located d in the upper die member S. Thestationary dies 29 and I then cooperate, and act as holding members whenthe upper and lower dies 9 and 8 are closed.

A crank shaft having all of the bearings and crank pins thereof in thesame plane is placed in the lower die 8 when the two dies are separated,or open. The crank shaft which is to be operated upon by the twistingmachine of the present invention consists of three main bearings and sixcrank pins. The two end bearings of the crank shaft are indicated by thenumerals 30 and 3l, and the center bearing is indicated at 32. The sixcrank pins of the crank shaft are indicated in Fig. 3 by the numerals33, 34, 35, 36, 3l and 38. Four crank pins 33, 35, S5 and 38 are all inalignment before the twisting operation is begun, the other two crankpins 3d and 3l also being in alignment. The crank shaft is placed in thedie in such a way that the center bearing 32, and the two intermediatecrank pins 35 and 36, are disposed in the stationary die or holdingmember I Ei. When the upper and lower dies are brought together, theholding member 29 in the upper die 9 will cooperate with the holdingmember IB in the lower die B to hold the crank pins 3&5 and St and thecenter bearing 32 against movement.

The outer crank pin 33 will be clamped between the rotating die ortwisting member 23 in the lower die 8, and the rotating twisting member25 of the upper die Likewise, the other outer crank pin 33 will beclamped between the rotating twisting member 2li of the lower die 8 andthe rotating twisting member 23 of the upper die 9. These rotatingtwisting members 23, 25 and 24, 2t may be referred to convenientlyhereinafter as the inner rotating twisting members. The other two crankpins 3Q and 3l will be disposed respectively in the outer rotatingtwisting members II and 2l, I2 and 28.

When the crank shaft is first placed in the lower die 8, the endbearings 36 and 3l will not be received within their respective twistingdies ZI, but will be twisted so as to be received by the die members 2iduring one of the twisting operations of the machine.

There are three distinct twisting operations in the operation of themachine. All of these twisting operations are accomplished by a singlestroke of the hydraulically operated actuating lever. Figs. 4 to 7,inclusive illustrate diagrammatically the manner in which the threethrows of the crank shaft are produced so that all of the bearings 3E),3l and 32 will be in alignment at the center of the finished crankshaft. The two crank pins 33 and 38 will be in alignment. The twointermediate crank pins 35 and 36 will be in alignment but one hundredand twenty degrees from the crank pins 33 and 38, and the two remainingcrank pins 3Q and 31, while being in alignment with each other, will belocated one hundred and twenty degrees from the other two pairs of crankpins, as illustrated in Fig. 7.

The method and manner of twisting the crank shaft to accomplish thisresult will be described first so that a clear understanding may be hadas to the objectives before a more detailed description is given withrespect to the other gures of the drawings. In Fig. 4, it will be notedthat the two crank pins 3!! and 31 are in alignment, and the threebearings 3c, 3l and 32 also are in alignment with each other and lieintermediate the crank pins 36 and 3l and the remaining crank pins.These remaining crank pins 33, 35, 36 and 38 also are all in alignmentwith each other before the twisting operation is begun.

The rst twisting operation is carried out by rotating certain of thecrank pins and bearings about the axis oi the crank pins 34 and 31 as acenter. Fig. 5 illustrates diagrammatically the appearance of the crankshaft at the end of the rst twisting operation, where the two outercrank pins 33 and 3B and the end bearings 30 and 3| have been movedthrough an arc of sixty degrees about the axis of the crank pins 34 and31 as a center. During this time the center bearing 32 and the othercrank pins 35 and 36 have been held in place by the holding members,

Iii and 29.

The second twisting operation moves certain of the crank pins andbearings about the axis of crank pins 35 and 36 as a center. In thissecond twisting operation, the crank pins 35 and 36, and the centerbearing 32, remain in place; while the outer crank pins 33 and 38, theend bearings 33 and 3i, and the intermediate crank pins 34 and 31 aremoved. through an arc of thirty degrees so that the result, at the endof the second twisting operation, appears as illustrateddiagrammatically in Fig. 6.

The final twisting operation takes place during the second twistingoperation and constitutes the movement of the end bearings 30 and 3|back into alignment with the center bearing 32, whereby the result willbe as illustrated diagrammatically in Fig. 7.

Summarizing briefly, the operations occur successively as follows:

First twisting operation During the rst twisting operation the innerrotating twisting members 23, 24, 25 and 26 rotate through sixty degreescausing the crank pins 33 and 38, and the end bearings 30 and 3|, to betwisted about the axis of crank pins 34 and 31 as a center. The endbearings 30 and 3| are in, or contained by,`their dies 2l at thebeginning of the rst stroke or twist, but are forced or twisted intoplace within their twisting dies 2| at the end of the first twist.

Second twisting operation The second twisting operation continues tomove the inner rotating twisting members 23, 24, 25 and 26, and movesalso the outer rotating twisting members Il, I2, 21 and 28 through anarc of thirty degrees. This movement of the twisting members carries thecrank pins 33, 38, 34 and 31 about the axis of crank pins 35 and St as acenter.

Third twisting operation The third twisting operation occurs during thesecond twisting operation. 'Ihe end bearings 3!) and 3| are notcontained within their twisting dies 2l until the end of the irsttwisting operation. The third twisting operation, therefore, constitutesa rotary movement of the twisting dies 2i which carries the end bearings36 and 3! about the axis of crank pins 33 and 38 as a center tobringthese end bearings 30 and 3l back into alignment with the center bearing32.

Fig. 9 illustrates the upper and lower dies Si and 8 respectively inclosed position after the rst twisting operation. The rotation of thetwisting dies is preferably carried on hydraulically, and for thispurpose a twisting cyl in d e r 39 is provided. The cylinder 39 isadapted to have hydraulic fluid forced therein from the pump 1 tooperate a piston. A piston rod 40 is connected to the piston which isarranged in the cylinder 39. The rod 40 is connected pivotally at 4l, toa yoke 42 which is secured to the rotating twisting members 23 and 24 ofthe lower die 8. This pivotal connection, and the formation of the yoke42, is shown in dotted lines in Fig. 3.

The upper and lower dies are illustrated in their open position in Fig.8. The inner twisting member 26 of the upper die 9v is a substantiallysemi-circular member, and may cooperate with the semi-circular twistingmember 24 of the lower die 8. The upper and lower twisting members 25and 23 are similarly arranged to cooperate with each other during thetwisting operation.

The outer rotating twisting member 2B of the upper die 9 has aconguration substantially like that shown in Fig. 8, being adapted tocooperate with the outer rotating twisting member l2 of the lower die 8.

The holding member, or stationary die member, 29 of the upper die 9, islikewise adapted to cooperate with the holding member l0 in the lowerdie 8. In the normal open position of the upper and lower dies theholding member 29, the inner rotating twisting members 25 and 26, andthe outer rotating twisting members 21 and 28, all have their lowerfaces in a common plane. The respective cooperating holding and twistingmembers of the lower die 8 also are arranged to have coplanar faces inthe normal open position of the upper and lower dies. Suitable recessesin the holding'and twisting members of the'upper and lower dies areprovided to receive the crank shaft. When the upper die is broughtdownwardly against the lower die, the coplanar faces of the elementsconstituting the upper dies, which are indicated by the numeral 43, willbe brought against the coplanar faces of the cooperating holding andtwisting members comprising the lower die, as indicated at 44.

Downward movement of the piston rod 49 carries with it the yoke 42 whichis secured to the kinner rotating twisting dies 23 and 24, so that thesetwisting dies 23 and 24, will be in the position indicated in Fig. 9.The inner rotating vdies 25y and 26 of the upper die will be caused torotate by cooperating with the twisting members 23 and 24, thereby toassume the position shown in Fig. 9.

During the rst twisting operation, the inner rotating twisting members23, 24, 25 and wili be the only ones which will move. As statedhereinabove, the end bearing twisting dies 2i do not contain the endbearings 3! and 3l until` the end of the iirst twisting operation. Fig.l() illu.:- trates the end bearing twisting dies 2l. and the lpositionof the end bearings 39 and 3! therein, at the end of the first twistingoperation.

The yoke 42 carries a lug 45 thereon, which lug 45 is adapted to comeagainst a face it ci the outer rotating twisting members I l and i2 inthe lower die 8. This lug 45 is shown clearly in Fig. 8, the two diesbeing separated; and Fig. 9 shows the lug 45 bearing against the face46.

Continued downward movement of the piston rod 40, and yoke 42, will thencause a rotation of the ,outer rotating twisting members il and IZ ofthe lower die because of the lug 45 bearing against the face 46. The endof the twisting operation is illustrated lin Fig. 11 wherein the lug 45is shown amante in contact with the face 45, the twisting members Il andI2 having been rotated through an angle of thirty degrees.

During this second twisting operation, the end bearing twisting dies 2|are rotated about the axis of crank pins 33 and 38 as a center, and thismovement of the end bearing twisting dies 2| is controlled by a link ilactuated by the movement of the inner rotating twisting members 23 and24. Fig. 12 illustrates the iinal position of the end bearing twistingdies 2l and the end bearings 30 and 3 I'.

After completion of the nal twisting operation, the upper and lower dies9 and 8 are opened to permit operation of the ejector mechanism whichincludes the lift-out rods 48 and 9. These rods 48 and 49 are positionedbelow the end bearings 3e and 3|, and are hydraulically actuated to moveupwardly and lift the completed crank shaft out of the lower die, asshown in Fig. 13. After .removal of the completed crank shaft from therods 48 and 49, the rods are moved downwardly, and the dies 8 and 9 areagain closed. The piston rod 4G is then moved upwardly to return all ofthe rotating twisting members of both the upper and lower dies to theiroriginal position. This completes one cycle of operation, and the twodies then may be opened and another forged lcrank shaft placed inposition to have the twisting operations formed thereon.

As Stated above, the details of the hydraulic system have not beenillustrated herein, but the operation of the press may be brieflysummarized as follows:

The operator will place a forged crank-shaft,

with all of the crank pins and bearings in the 'same plane, into thelower die 8 when the dies are open. The operator then may depress acycle button, to cause the press to begin its downward stroke. When theupper die has reached the lower die, pressure is built up in the maincylinder of the hydraulic system. After a predetermined amount ofpressure has been reached a sequence valve automatically will direct'vthe ow of hydraulic fluid from the pump l into the hydraulic cylinder39. This will cause the piston and its attached piston rod t!) to movedownwardly and rotate the inner twisting members 23, 24, 25 and 26,causing crank pins 33 and 38 and end bearings 39 and 3l to swing sixtydegrees about the center of crank pins 34 and 31.

This twisting action will thereupon move the end bearings 3S and 3l intotheir `respective twisting dies 2i. The piston rod d0 will continue inits downward movement, whereupon 'the lugs or projections, either on theyoke 42 or on the inner twisting members, will contact the outerrotating twisting members H and l2 and cause the inner and outerrotating twisting members ito `rotate together. This latter rotation o'fall of the twisting members will cause a twisting of crank pins 33, 38,34 and 31 about the center of crank pins 35 and 35. Also, during thislatter movement and operation, the twisting dies '2i containing .the endbearings 3l! and 3i, will twist the end bear-- ings 39 and '3i about thecenter of lcrank pins and 38 and move them into alignment with .thecenter bearing '32.

The twisting stroke is then completed, and the press will openautomatically as shown in Fig. 13. During the upstroke of the upper Adiethe lift-out rods 48 and 49 will move upwardly through the bed and raisethe completed crank shaft out of the lower die. The crank shaft is thenremoved vand the lift-out rods-drop back into the'lower-die's by thenoperation of an independent air valve. The press is then closed beforeanother crank shaft is placed therein, and the piston rod is caused tomove upwardly to reverse the procedure just described for the purpose ofreturning all of the twisting members to their original position. Thepress again opens automatically and is then ready for loading anothercrank shaft.

Changes may be made in the form, construction and arrangement of partsand the method maybe varied within certain degrees herein withoutdeparting from the spirit of the invention or sacricing any of theattendant advantages thereof, provided, however, that such changes fallwithin the scope. of the claims .appended hereto.

Having thus described my invention what I `claim as new .and desire tosecure by Letters Patent of the United States is:

1. A crank shaft twisting machine comprising a pair of dies movable toopen andclosed positions and adapted to receive a crank shaft whereinthe bearings and crank pins are all in the same plane, cooperatingstationary holding members in said .dies adapted to engage and hold thecrank shaft, cooperating rotating twisting members in said vdies eachadapted to engage a different crank pin on the crank shaft for twisting,means operable upon one of the twisting members of .one .die forrotating .said .one twisting member and its cooperating twisting Amemberin the other die when the .dies yare closed thereby twisting the .crankpins in said :one twisting member out of the planes of .the other crank.pins and bea-rings, and 'means on said .one twisting member adapted tocooperate with the other twisting member of the same die for rotatingsaid other twisting member and its cooperating twisting member in theother die after said one twisting member has been rotated through apredetermined rarc thereby twisting the crank pins in said othertwisting members out of the Lplanes of the remaining crank pins vandbearings.

2. A crank shaft twisting machine comprising a .pair of dies movable toopen and closed posid tions and adapted to receive a crank shaft whereinthe bearings and crank `pins are all Yin .the same plane, cooperatingstationary holding members in said dies adapted to engage and hold thecrank shaft, cooperating rotating twisting members in Vsaid dies eachadapted to engage a different Vcrank pin on the .crank shaft fortwisting, means operable upon one of the twisting members of one die-for Yrotating said one twisting member and its cooperating twistingvmember .in the other die when the dies are closed thereby twisting thecrank pin in said one twisting member out of the plane of the othercra-nk pins, .and means on said one twisting member adapted to cooperatewith the other twisting member of the 'same .die for :rotating saidother twisting member and itscooperating twisting member in the .otherdie .after-.said one twisting member has been rotated through apredetermined arc and during `continued rotation of said one twistingmember.

i3. A .crank shaft twisting machine comprising va pair Vof separabledies .adapted to receive acrank shaft wherein the 'bearings and crankpins are all in the sm@ plane, cooperating holding members in said-d-ies adapted Ato hold intermediate crank pins of a crank shaft,cooperating rotating twist- :ing members 'in said .dies each Vadapted toengage a-:di'ierent-crankipinonthe crank shaft for twisting', means--operable upon Yone of the twisting members of lone of the `dies -rorrotating vsaid one rltwrsting mem-ber and vits cooperating twistingmember in the other die when the dies are closed thereby twisting thecrank pin in said one twisting member out of the plane of the othercrank pins and bearings, means for rotating the other twisting membersafter said one twisting member has been rotated through a predeterminedarc, and a twisting die for each end bearing of a crank shaft, and meanswhereby said rst named means also positions the ends of a crank shaftwithin said twisting dies.

4. A crank shaft twisting machine comprising upper and lower diesmovable to open and closed positions and adapted to receive a crankshaft wherein the bearings and crank pins are all in the same plane,cooperating holding members in said dies adapted to engage and hold thecrank shaft, cooperating rotating twisting members in said dies eachadapted to engage a diierent crank pin on the crank shaft for twisting,means operable upon one of the twisting members of said lower die forrotating said one twisting member and its cooperating twisting member inthe upper die when the dies are closed thereby twisting the crank pin insaid one twisting member out of the plane of the other crank pins, meansfor rotating the other twisting member of the lower die and itscooperating twisting member in the upper die during a portion of therotating movement of said one die, and a twisting die for each endbearing of a crank shaft, and means whereby said rst named means alsopositions the end bearings of a crank shaft within said twisting dies.

5. A crank shaft twisting machine comprising upper and lower diesmovable to open and closed positions and adapted to receive a crankshaft therein wherein the bearings and crank pins are all in the sameplane, cooperating stationary holding members in said dies to holdcertain of the crank pins and bearings of the crank shaft againstmovement, cooperating inner rotating twisting members in said diesadapted to engage certain of the crank pins of the crank shaft to twistcertain of the crank pins of the crank shaft about a predetermined axis,cooperating outer rotating twisting members in said dies adapted toengage certain other crank pins .on the crank shaft to twist saidcertain other crank pins of the crank shaft about a predetermined axis,means operable upon the inner rotating twisting members of one of saiddies to rotate the inner rotating twisting members of both of said dies,and means vfor rotating the outer twisting members of both of said diesafter the inner rotating twisting members have been rotated through apredetermined arc.

6. A crank shaft twisting machine comprising upper and lower diesmovable to open and closed positions and adapted to receive a crankshaft -therein wherein the bearings and crank pins are all in the sameplane, cooperating stationary holding members in said dies to holdcertain of the crank pins and bearings of the crank shaft againstmovement, cooperating inner rotating twisting members in said diesoperable to twist certain of the crank pins of the crank shaft about apredetermined axis, cooperating outer rotating twisting members in saiddies operable to twist certain other crank pins of the crank shaft abouta predetermined axis, means operable upon the inner rotating twistingmember of the lower die to rotate the inner rotating twisting members ofboth of said dies, and means for rotating the outer twisting members ofboth of said d ies during a portion of the rotating movement of theinner twisting members.

CII

'7. A crank shaft twisting machine comprising upper and lower diesmovable to open and closed positions and adapted to receive a crankshaft therein wherein the bearings and crank pins are all in the sameplane, cooperating stationary holding members in said dies to holdcertain of the crank pins and bearings of the crank shaft againstmovement, cooperating inner rotating twisting members in said diesoperable to twist certain of the crank pins of the crank shaft about apredetermined axis, cooperating outer rotating twisting members in saiddies operable to twist certain other crank pins of the crank shaft abouta predetermined axis, means operable upon the inner rotating twistingmember of the lower die to rotate the inner rotating twisting members ofboth dies through an arc of substantially and means for rotating theouter twisting members of both of said dies together with the innertwisting members through substantially the last 30 of said 90.

8. A crank shaft twisting machine comprising upper and lower diesmovable to open and closed positions and adapted to receive a crankshaft therein wherein the bearings and crank pins are all in the sameplane, cooperating stationary holding members in said dies to hold thecenter bearing and the pair of crank pins adjacent said center bearingof the crank shaft against movement when said dies are closed,cooperating inner rotating twisting members in said dies to receive andtwist a second pair of crank pins about a predetermined axis,cooperating outer rotating twisting members in said dies to receive andtwist a third pair of crank pins about a predetermined axis, meansoperable upon the inner twisting member of said lower die to rotate theinner twisting members of both dies, and means for rotating the outertwisting members of both dies during a portion of the rotating movementof said inner twisting members.

9. A crank shaft twisting machine comprising upper and lower diesmovable to open and closed positions and adapted to receive a crankshaft therein wherein the bearings and crank pins are all in the sameplane, cooperating stationary holding members in said dies ot hold thecenter bearing of the crank shaft and the pair of crank pins adjacentthereto against movement when said dies are closed, cooperating innerrotating twisting members in said dies to receive and twist asecond`pair of crank pins about a predetermined axis, cooperating outerrotating twisting members insaid dies to receive and twist a third pairof crank pins about a predetermined axis, means operable to rotate rstthe inner -twisting members and then the outer twisting members, endbearing twisting members adapted to receive and twist the end bearingsof the crank shaft about a predetermined axis, the end bearings of thecrank shaft being normally positioned out of said end bearing twistingmembers and movable into said end bearing twisting members during therst rotation of said inner twisting members.

l0. A crank shaft twisting machine comprising upper and lower diesmovable to open and closed positions and adapted to receive a crankshaft therein wherein the bearings and crank pins are all in the sameplane, cooperating stationary holding members in said dies to hold thecenter bearing of the crank shaft and the pair of crank pins adjacentthereto against movement when said dies are closed, cooperating innerrotating twisting members in said dies to receive and twist a secondpair of crank pins about a predetermined axis, cooperating outerrotating twisting members in said'dies to receive and twist a third pairof crank pins about a predetermined axis, means operable to rotate rstthev inner twisting members and then the outer twisting members, endbearing twisting members adapted to receive and twist the end bearingsof the crank shaft about a predetermined axis, the end bearings of thecrank shaft being normally positioned out of said end bearing twistingmembers and movable into said end bearing twisting members during thefirst rotation of said inner twisting members, and means lfor rotatingsaid end bearing twisting REFERENCES CITED The following references areof record in the file of this patent:

UNITED STATES PATENTS Name Date Damerell Aug. 6, 1918 Number

